Stero configurations of 3((2-mercapto-1-methylpropyl)thio)-2-butanol

ABSTRACT

The flavor of a foodstuff is altered by use of one of the four compounds, the structure of which is one of the configurations of 3((2-mercapto-1-methylpropyl) thio)-2-butanol represented by the structures:   Each of these configurations produ

United States Patent Evers et al.

[451 Sept. 23, 1975 STERO CONFIGURATIONS OF 3( (Z-MERCAPTO- l-METHYLPROPYL )THI- O)-2-BUTANOL [75] Inventors: William John Evers,Atlantic Highlands; Manfred Hugo Vock, Locust, both of N.J.; IgorAlexander Pelse, Elmhurst, N.Y.

[73] Assignee: International Flavors & Fragrances Inc., New York, N.Y.

[22] Filed: Aug. 23, 1974 [21] Appl. No.: 499,898

[52] US. Cl 260/609 R; 426/65; 426/175; 426/203; 426/221; 426/222;426/342 [51] Int. Cl. A23L l/26; C07C 149/18 [58] Field of Search260/609 R [56] References Cited UNITED STATES PATENTS 3,390,186 6/1968Normant 260/609 A 3,567,782 3/1971 Warner et al. 260/609 R 3,635,736l/l972 Oftedahl 260/609 R 3,653,920 4/1972 Brinkrnan et al 260/609 A3,686,329 8/1972 Bernhart 260/609 D 3,717,682 2/1973 Geering et al.260/609 D Primary Examiner-Lewis Gotts Assistant ExamirierD. R. PhillipsAttorney, Agent, or F irm-Arthur L. Liberman Esq.;

Harold Haidt, Esq.

ABSTRACT (It I H I (ThrOO-Threo; (U)

w (Erythro -Thrlo; (II I) (Thrao -Erythr0; (Ill) H SH I c I c e H(Erythm- Erythro; (lVl structures:

V (Erythro) H OH SH l l l c V (Ery'hro) H 9 SH I II H C H CH VI (Three)I Ho 1 l c Vl (Threel 5 Claims, 8 Drawing Figures US Patent Sept.23,1975 Sheet 1 of8 3,907,906

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a m n s xu N w m US Patent STERO CONFIGURATIONS OF 3( 2-MERCAPTO-l-METHYLPROPYL )THIO )-2- BUTANOL BACKGROUND OF THE INVENTION Thisinvention has to do with altering the organoleptic properties offoodstuffs. More particularly, the invention relates to the use ofcertain configurations of 3( Z-mercaptol -methylpropyl) thio )-2-butanolhaving the structures:

(Thre o Threo (ll) (Throo -Eryfhro;

(Erythro -Threo;

(Ill) (Eryihro- Erythro;

to alter the flavor characteristics of a foodstuff. Contemplated areprocesses and compositions for altering the flavor of foodstuffs andprocesses for preparing the said 3((2-mercapto-l-methylpropyl)thio)-2-butano1 configurations.

The term alter in its various forms is used herein to mean the supplyingor imparting of a flavor or aroma characteristic or note to an otherwisebland, relatively tasteless or non-odorous substance, or augmenting anexisting flavor or aroma characteristic where the natural flavor orintrinsic odor is deficient in some regard, or supplementing theexisting flavor or aroma impression to modify its quality, character,taste or aroma.

tinuing search by those engaged in the production of foodstuffs. Theshortage of foods, especially protein foods, in many parts of the worldhas given rise to a need for utilizing non-meat sources of protein andfor making such protein as palatable and meat-like as possible. Inaddition, various techniques utilized in processing food detract fromtheir flavor quality or give rise to off-flavors. Convenience or snackfoods are increasing in volume and they require flavoring. Accordingly,materials capable of closely simulating, improving, or even exactlyduplicating the flavor and The term foodstuff as used herein includesboth solid and liquid ingestible materials which usually do, but neednot have nutritional value, Thus, food-stuffs include meats, gravies,soups, convenience foods, beverages, dairy products, candies,vegetables, cereals, soft drinks, snacks and the'like. v

The reproduction of roasted meat, liver and alliacious flavors has beenthesubject of a long and con- (Threo-Threo (In r aroma of roastedproducts and roasted meat, liver and alliacious (e.g., onion and garlic)products have long been sought.

PRIOR ART Various alkane thiols and alkane mercapto sulfides have beensuggested as flavoring agents. Thus, U.S. Letters Pat. No. 3,653,920which issued on Apr. 4, 1972 states that certain alkane thiol sulfides,such as 2-thiobutane thiol, can be used to impart a meat flavor tofoods; and U.S. application Ser. No. 135,337, filed Apr. 19, 1971 nowU.S. Pat. No. 3,713,848, describes various branched chain alkane thiols,such as 2-methyl- 3-butane thiol, and suggests their use for impartingroasted meat aroma and taste. 3((2-Mercapto-1- methylpropyl)thio)-2-butanol, broadly, is taught as a flavoring agent in copendingapplication for U.S. Let ters Pat. Ser. No. 354,304 filed on Apr. 25,1973 but the specific organoleptic attributes of the four followingconfigurations of 3((2-mercapto-l-methylpropyl) thio)-2-butanol are notdisclosed.

(Three -Erythro; (In) (Eryfhro -Threo; (l l') (Erythro- Eryfhro;

SUMMARY OF THE INVENTION In accordance with this invention a series offour sul fur-containing compounds having four configurations of3((2-mercapto-l-methylpropyl) thio)-2-butanol have been provided foraltering the roasted meat, liver or alliacious flavor of foodstuffs.These configurations of 3( Z-mercaptol -methylpr0pyl) thio)-2-butanoluseful in this regard may be represented by the following structures:

DESCRIPTION OF THE PREFERRED EMBODIMENTS The3((2-mercapto-l-methylpropyl) thio)-2-butanol configurations of thisinvention are primarily useful in roasted meat, liver and aliaciousflavor compositions. They are especially suitable as flavors by reasonof the wide range of useful concentrations at which they can be applied.Most flavor chemicals become objectionable in character at some pointnot too greatly above (Three-Three; (H) (Three -Erythro;

HO s

I CH I H H3C H CH3 (Ill) (Erythro- Erythro;

(Erythro -TI-|roo;

Each configuration is prepared by reacting a cis or trans 2,3-butaneepisulfide with an erythro or three 2-hydroxy-3-mercapto butane havingone of the structures:

V (Erythro) VI (Three) These structures may also be represented asfollows:

l HO l l c V (Erythro) v| (Three) their threshold value. The3((2-mercaptol-methylpro pyl) thio)-2-butanol configurations of thepresent inventtion have been found to be still suitable versatile andinoffensive at proportions well in excess of their threshold value andsubstantially above the multiple of their threshold at which otherflavor chemicals are objectionable.

The threshold value of the 3((2-mercapto-l-methylpropyl) thio)-2-butanol configurations may range from 0.1 parts per million to 0.2parts per million and, therefore, normally would be used at levels offrom about 0.1 parts per million to about 10 parts per million, but canactually be used without imparting an objectionable character up toabout 30 parts per million based on the total weight of the foodstuff.

.5, 'lheactualamountused 'wi ll vary depending upon a variety of'factorsincluding the particulanflavoring agent usedithe flavoreffect desired,considerations, the amount andptype of other-ingredients present, thefoodstuff to be flavored and the processing and methylpropyl) thio)-storage conditions to which the f H stuffv will be subjected. It shouldbekept in mind that larger concentra-' tions do not necessarily giveequivalent incremental flavor enhancement. In those instances where theparticular 3((Z-mercapto-l-methylpropyl) thio)-2-butanol l0 TABLE ICompound: Structure:

Erythro-Erythro 3( Z-mercaptol -me thylpropyl) thio )-2-butanol S H H CH Flavor Character:

At 0.1 ppm, sulfury, roasted weak metallic taste.

At 0.5 ppm, sulfury, metallic, heat oniony taste, weak, burning, onionyafter taste.

Use Concentration:

0.1 ppm Compound: Erythro-Threo 3( 2-mercaptol methylpropyl) thioZ-butanol Structure:

Flavor Character: Use Concentration:

At 0.1 ppm, sulfury, 0.1 10 ppm roasted, metallic taste; slightlystronger than erythro-erythro 3( Z-mercaptol -rnethyl propyl) thio)-2-butanol. At 0.5 ppm, sulfury, roasted, metallic, weak, bloody,hydrolyzed vegetable protein-like after taste; but no oniony notes.

i TABLE I-continued Compound: Threo-Erythro 3( 2-rnercaptol Structure:

2-butanol Flavor Character:

At 0.1 ppm, a sweet, roasted, metallic, liver-like taste;

At 0.5 ppm, stronger liver-like and roasted notes.

Use Concentration: O.l ppm 20 ppm Compound: Threo-Threo 3((2- mercapto-1 -methylpropyl) thio)-2- butanol Structure:

Flavor Character:

At 0.2 ppm only garliclike notes; no meaty notes;

At 0.5 ppm, characteristic garlic aroma and taste; roasted notes with aburning after taste;

At 1.0 ppm strong garlic metallic, roasted garlic notes.

Use Concentration:

0.1 30 ppm The 3((2-mercapto-l-methylpropyl) thio)-2-butanolconfiguration contemplated as flavoring agents by the present inventionare novel compounds and are prepared by the novel processes of thisinvention as further exemplified herein, 1 I

The structures set forth in illustrating the3((2-mercapto-l-methylpropyl) thi0)-2-butar1ol configurations .of ourinvention are each intended to represent single and in admixture opticalisomers of each particular configuration. Thus, for example, thestructure:

illustrating erythro-erythro 3 Z-mercapto- 1 -methylpropyl)thio)-2-butanol is intended to read singly and in admixture theresultant racemates each of which is made up of a dextro and laevorotatory form.

The process of our invention involves the reaction of cis or trans2,3-butane episulfide with erythro 3-mercapto-2-butanol or three3-mercapto-2- butanol. The particular resulting3((2-mercapto-lmethylpropyl) thio)-2-butanol configuration is directlydependent on whether the cis or trans 2,3-butane episulfide is reactedwith the erythro or threo 3- mercapto-2-butanol.

Hence, erythro-erythro 3( 2-mercapto- 1 -methylpropyl) thi)-2-butanol(or erythro-erythro form) having the structure:

is produced by reacting erythro-3-mercapto-2-butanol withtrans-2,3-butane episulfide. Erythro-threo 3((2-mercapto-l-methylpropyl) thio)2-butanol (or erythro-threo form) havingthe structure:

H HO I 5 SH I 'IICH H H CH3 is produced by reactingerythro-3-mercapto-2butanol with cis-2,3-butane episulfide. Three-threo3((2-mercapto-l-methylpropyl) thio)-2-butanol (or threothreo form)having the structure:

is produced by reacting threo-3-mercapto-2-butanol is produced byreacting threo-3-mercapto-2-butanol with trans-2,3-butane episulfide.

V (Erythro) HO H SH H C H CH3 -V (Erythro The reaction of the three orerythro 3-mercapto-2- butanol with the cis or -trans=2',3-butaneepisulfide is carried out in the presence of an amine base catalyst suchas methyl amine, ethyl amine -piropyl amine, dimethyl amine, diethylamine, ethanol amine, diethanolamine. triethanolainine, triethanol aminepyride, piperidine, pyraz ine, picbIirieQaniIine trimethyl amine,pyrolle, methyl pyrazine, 2,3-dimethyl pyrazine, l-methyl pyrrole andl-phenyl pyrrole. A preferred catalyst is diethyl amine because of itslow cost and ease of availability.

The catalyst concentration is preferably from 0.1% up to 1.0% with aconcentration of 0.5% being preferred.

The reaction temperature range is from 25C up to 80C with a temperaturerange of -60C being preferred.' i

The preferred mole ratio of reactants is 1:] but mole ratios ofepisulfide:mercaptobutanol of from 0.25:1 up to 1:5 are operable.

It is also preferable that the reaction be carried out in an inert (ornonreactive) solvent which is usable with the desired reactiontemperature range of 25 up to C. Such a solvent is methanol; but othersolvents having boiling points at atmospheric pressure greater than 50Care usable such as ethanol, isopropanol, isobutyl alcohol,tetrahydrofuran and cyclohexanol.

The concentration of reactant in solvent may vary from 10 gm/liter up to500 gm/liter with a concentration range of 30100 gm/liter (totalquantity of reactant/total solvent) being preferred.

At the end of the reaction, the reaction mass is aciditied in order toneutralize the amine catalyst. The reaction mass is then worked-up usingstandard unit operations such as extraction, drying, evaporation andfractional distillation.

The erythro and threo 3-mercapto-3-butanol compounds which are reactantshaving the structure:

which may also be represented as follows:

are prepared by reaction of hydrogen sulfide with cis or trans2,3-epoxybutane.

Erythro-3-mercapto-2-butanolis prepared by reacting H 8 withtrans-2,3-epoxybutane. Threo-3-mercapto-2-butanol is prepared byreacting cis-2,3-epoxybutane with H 8.

The reaction is preferably carried out at atmospheric pressure and atemperature in the range of 5060C in an inert solvent such as a loweralkanol; preferably methanol and in the presence of an amine catalyst,such as methyl amine, ethyl amine, pyridine, pyrazine, pyrrole anddiethyl amine. Diethyl amine is preferred. At the end of the reaction,the reaction mass is aciditied so as to neutralize the amine catalyst;and worked-up by means of such standard unit operations as extraction,drying, evaporation, and fractional distillation.

The concentration of 2,3-epoxybutane reactant in solvent may vary from10 g/liter up to 500 g/liter with a concentration range of 30l00 g/literbeing preferred.

The catalyst concentration is preferably from 0.1% up to 1.0% with aconcentration of 0.5% being preferred.

The 3( Z-mercaptol -methylpropyl) thio)2-butanol configurationsdescribed herein may be employed either singly or in admixturescomprising two or more thereof. Admixtures of two or more(3((2-mercapto-lmethylpropyl) thio)-2 -butanol configurations offer theadvantages of combining the beneficial and organoleptic qualities ofeach of the compounds into a total impact which is superior or differentfrom the characteris tics of the sole ingredient. The formulator cansimulate a wide variety of organoleptic characteristics to evoke apredetermined taste response on the part of the consumer.

Generally in use the 3((2-mercapto-l-methylpropyl) thio)-2-butanolconfigurations are admixed with one or more auxiliary flavoringadjuvants. The precise adjuvants employed will depend upon the ultimateuse con templated and the organoleptic character desired. Flavoringadjuvants are recognized in the art and are ingestibly acceptable ornon-toxic. Such flavoring adjuvants include stabilizers, thickeners,surface active agents, conditioners, flavorants and flavor intensifiers.

Stabilizers include preservatives, e.g., sodium chloride, antioxidants,e.g., calcium and sodium ascorbate, ascorbic acid, butylatedhydroxyanisole (mixture of 2 and 3 tertiary butyl-4-hydroxyanisole),butylated hy droxy toluene (2,6-di-tertiary-butyl-4-methyl phenol),propyl gallate and the like, sequestrants, e.g., citric acid.

Thickeners include carriers, binders, protective colloids, suspendingagents, emulsifiers and the like, e. g., agar-agar; carrageenan;cellulose and cellulose derivatives such as carboxymethyl cellulose andmethyl cellulose; natural and synthetic gums such as gum arabic, gumtragacanth; and proteinaceous materials such as gelatin; lipids,carbohydrates; starches; pectins and emulsifiers, e.g., monoanddiglycerides of fatty acids.

Surface active agents include emulsifying agents, e.g., fatty acids suchas capric acid, caprylic acid, palmitic acid, myristic acid and thelike, monoand diglycerides of fatty acids, lecithin, defoaming andflavordispersing agents such as sorbitan monostearate, potassiumstearate; hydrogenated tallow alcohol and the like.

10 Conditionersinclude compounds such as bleaching and maturing agents,e.g., benzoyl peroxide, calcium peroxide, hydrogen peroxide and thelike; starch modifiers such as peracetic acid, sodium chlorite, sodiumhypochlorite, propylene oxide, succinic anhydride and the like; buffersand neutralizing agents, e.g;, sodium acetate, ammonium bicarbonate,ammonium phosphate, citric acid, lactic acid, vinegar and the like;colorants, e.g., carminic acid, cochineal, tumeric and curcumin and thelike; firming agents such as aluminum sodium sulfate, calcium chlorideand calcium gluconate; texturizers; anti-caking agents, e.g., aluminumcalcium sulfate and tribasic calcium phosphate; enzymes; yeast foods,e.g., calcium lactate and calcium sulfate; nutrient supplements, e.g.,iron salts such as ferric phosphate, ferric pyrophosphate, ferrousgluconate and the like, riboflavin; vitamins; zinc sources such as zincchloride, zinc sulfate and the like.

Flavorants and flavor, intensifiers include organic acids, e.g., fattysaturated, unsaturated and amino acids; alcohols, e.g., primary andsecondary alcohols; esters; carbonyl compounds including aldehydes andketones; lactones; cyclic organic materials including benzenederivatives; alicyclics, heterocyclics such as furans, pyridines,pyrazines and the like; sulfur-containing materials including thiazoles,thiols, sulfides, disulfides and the like; so-called flavor potentiatorssuch as monosodium glutamate, guanylates, inosinates; natural andsynthetic flavorants such as vanillin, natural gums and the like;spices; herbs; essential oils and extractives including anise, aniseoil, alkanet root extract, bay leaves, capsicum extract and the like.

, The specific flavoring adjuvant selected for use may be either solidor liquid, depending upon the desired physical form of the ultimateproduct, i.e., foodstuff, whether simulated or natural, and should, inany event, be capable of providing an environment in which the3((2mercapto-l-methylpropyl) thio)-2-butanol configurations can bedispersed or admixed to provide a homogeneous medium. In addition,selection of one or more flavoring adjuvants as well as the quantitiesthereof will depend upon the precise organoleptic character desired inthe finished product; thus, in the case of flavoring compositions,ingredient selection will vary in accordance with the foodstuff to whichthe flavor and aroma are to be imparted. ln contra-distinction, in thepreparation of solid products, e.g., simulated foodstuffs, ingredientscapable of providing normally solid compositions should be selected suchas various cellulose derivatives.

The preferred flavoring adjuvants which are used in combination with atleast one 3( Z-mercapto- 1 -methylpropyl) thio)-2-butanol configurationinclude: 4-methyI-S-(beta-hydroxy ethyl) thiazole, ethyl thioacetate,furfural, benzaldehyde, methional, hexanal, diacetyl, amyl alcohol,ethyl disulfide, methyl mercaptan, 2,4- decadienal, 2,4-decadienol,2,5-dimethyl-2,5-dihydroxy-l,4-dithiane, 1,3-dithiolane,2-methyl-l,3-dithiolane, 3,5-dimethyl-1,2-dithiolane,3-methyl-l,2-dithiolane, 2,4-dimethyl-1,3-dithiolane,4-methyl-l,3-dithiolane, l,-2-dithiane, 1,3-dithiane, l,4dithiane,2-methyl-l ,3'-dithiane, 2;4-dimethylb l ,3 -dithiane, 4-methyl-1,3-dithiane, 2,4,6-trimethyl-l ,3-dithiane, thiamine hydrochloride,Z-methyl-l-butanethiol, 4-rnercapto-2- butanone, 3-mercapto-2-pentanone,furfuryl alcohol, 2-mercapto propionic acid, methyl pyrazine, 2-ethyl-3-methyl pyrazine, tetrahydrofurfuryl alcohol,.tetrahy-'drothiophen-3-one, tetramethyl pyrazine, dipropyl disulfide, methylbenzyl disulfide, 2-butyl thiophene, 2,3- dimethyl thiophene,S-methylfurfural, 3-acetyl-2,5- dimethyl-furan, guaiacol, phenylacetaldehyde, deltadecalactone, d-limonene, acetoin, amyl acetate,maltol, ethyl but-yrate, levulinic acid, piperonal, ethyl acetate,noctanal, n-pentanal, 2-isobutyl thiazole, propyl propenyl disulfide,3-mercapto-2,5-dimethylfuran, methyl- 3-(2,5-dimethylfuryl) disulfide,propyl propenyl trisulfide, 2,6-dimethyl pyrazine, acetophenone,2-methyl-2- butenal, furfuryl mercaptan, acetyl propionyl,3-thioacetyl2,5-dimethylfuran, bis-3-(2,5-dimethylfuryl) disulfide andbis-3-(2-methylfuryl) disulfide.

Flavoring compositions prepared in accordance with the present inventionpreferably contain one or more 3((2-mercapto-l-methylpropyl)thio)-2-butanol configurations in concentrations ranging from about 1 Xto 25% by weight, based on the total weight of said flavoringcompositions, but may contain as much as 80 or 90% by weight of the3((Z-mercapto-l-methylpropyl) thio)-2-butanol configuration, if theflavoring composition is then applied in small amount.

All parts, proportions, percentages and ratios herein are by weightunless otherwise indicated.

It will be understood by those skilled in the art that the alkanedithiol, mercapto alkanol, alkane dimercapto sulfide and alkane hydroxymercapto sulfide can be added to the materials to be flavored oraromatized at any convenient point in the production of the consumablematerial by any of the conventional techniques including spray drying,blending, stirring, dis solving and the like. Thus, when they are usedto alter or otherwise vary the flavor of a foodstuff, they can be addedin the original mixture, emulsion, preparation, or the like, prior toany cooking or heating operation. Alternatively, they can be added at alater stage of processing if volatilization losses would be excessiveduring the earlier processing.

The following examples are given to illustrate embodiments of theinvention as it is now preferred to practice it. It will be understoodthat these examples are illustrative, and the invention is not to beconsidered as restricted-thereto except as indicated in the appendedclaims.

EXAMPLE I SYNTHESIS OF ERYTHRO-3-MERCAPTO-2-BUTANOL Into a 250 mlthree-necked flask equipped with heating mantle, condenser, hydrogensulfide addition tube and magnetic stirrer, the following materials areadded:

maintaining the temperature at 56C. At the end of the 6.5 hour period, H5 addition ceases and the reaction mass is allowed to remain at roomtemperature overnight. The reaction mass is then heated to 54C, and anadditional 4.5 grams of trans-2,3-epoxybutane is added while maintainingthe reaction mass at a temperature of 54C. The reaction mass is heatedto 54C for a period of 5 hours. At the end of 3 hours, 1.3 grams ofadditional trans-2,3-epoxybutane is added.

The reaction mixture is then poured into 100 cc of water. To this mass,dilute hydrochloric acid is added until the reaction mass is slightlyacidic. The reaction mass is then extracted with two portions ml each)of methylene dichloride, dried and concentrated to 6.4 grams of crudeoil. The 6.4 grams of crude oil is charged to a micro-distillation setup, and distillation is carried out at a temperature of 5153C at 10 mmHg pressure. The resulting material is the erythro form of3-mercapto-2-butanol, having the structure:

EXAMPLE II SYNTHESIS OF THREO FORM OF 3-MERCAPTO-2-BUTANOL Into a 250 mlthree-necked flask equipped with heating mantle, condenser, hydrogensulfide addition tube and magnetic stirrer, the following materials areadded:

Ingredients Parts Ingredients Parts Diethyl amine 0.5 cc Methanol 100 ccMethanol 100 ml Diethyl amine 1 cc The reaction mass is heated to 44Cand bubbling of hydrogen sulfide through the solution is then commenced,At the end of 1 hour, at a temperature of 55C, 1.7 grams ofcis-2,3-epoxybutane is added to the reaction mass. At the end of 3 hoursat a reaction temperature of 58C, H 5 addition is ceased, and thereaction mass is allowed to remain overnight at room temperature. Thereaction mass is then heated to 5 l5 7C and maintained at thattemperature for a period of 5 hours while adding hydrogen sulfide. Atthe end of l 13 hour, at a reaction temperature of 55C, 1.7 grams ofcis-2,3-epoxybutane is added. 2.7 grams of cis-2,3- epoxybutane is addedat the end of 2 hours.

The reaction mass is then poured into 100 ml diluted hydrochloric acid(2%) thereby. causing the reaction EXAMPLE III SYNTHESIS OF THECIS-ISOMER OF 2,3-BUTANE EPISULFIDE FROM CIS-2,3EPOXYBUTANE l 1.0 Gramsof cis-2,3-epoxybutane is added to a stirring solution of 13 grams ofKSCN in 10 ml water and 7 ml 95% aqueous ethanol. The solution turns alight greenish-yellow. At the end of 6 hours, the reaction mass is nolonger stirred. Thereaction mass remains quiescent overnight. Thereaction mass is then stirred over a period of 8 hours and then allowedto remain quiescent overnight.

Six grams of KSCN, 10 ml water and 5 ml aqueous 95 ethanol are thenadded to the reaction mass which is stirred for a period of 4.5 hours.

The reaction mass (organic layer) is then dried over anhydrous sodiumsulfate and distilled in a micro-distillation apparatus at 39C and 125mm Hg pressure yielding the cis isomer of 2,3-butane episulfide, havingthe structure: J

EXAMPLE IV SYNTHESIS OF TRANS ISOMER OF 2,3-BUTANE EPISULFIDE FROM TRANS2,3-EPOXYBUTANE Eleven Grams of trans-2,3-epoxybutane is admixed with 13grams KSCN, 10 ml water and 7 ml aqueous ethanol. The reaction mass isstirred at room temperature for a period of 2 days. Six Grams of KSCN,10 ml water and 5 ml 95% aqueous ethanol is then added to the reactionmass which is stirred for another 24 hours. The reaction mass is thenallowed to remain quiescent for a period of 5 days. The upper organicphase is then removed and dried over anhydrous sodium sulfate anddistilled at 33C and 95mm Hg pressure yielding the trans isomer of2,3-butane episulfide, having the structure:

EXAMPLE V SYNTHESIS OF ERYTHRO-ERYTHRO 3 Z-MERCAPTO- l-METHYLPROPY L)THIO )-2-BUTANOL is isolated via preparatory gas liquid chromatographyon 8 feet X A inch glass 5% Carbowax 20M (polyethylene glycolterminated, with terephthalic acid), and analyzed by mass spectralanalysis, NMR analysis and IR analysis which confirm the aforementionedstructure. FIG. '1 is the NMR spectrum for this material. FIG. 2 is theinfrared spectrum for this material.

EXAMPLE VI SYNTHESIS OF ERYTHRO-THREO 3( Z-MERCAPTO- l-METI-IYLPROPYL)THIO)-2-BUTANOL To a solution of methanol (25 cc) and diethyl amine (10drops) at 50C is added 1.0 g of erythro 3-mercapto-2-butanol (Example I)and cis-2,3-butane episulfide which is then stirred at a temperature of50C for a period of 2 hours. The reaction mass is then allowed to remainovernight at room temperature after which period 15 1 of time is heatedfor a period of 8 hours at 50C. The reaction mass is then allowed toremain overnight after which time it it is heated to 50C and caused toremain at 50C with stirring over a period of 8 hours. When 1 FIG. 3 isthe NMR spectrum for this material. FIG. 4 is the infrared spectrum forthis material.

EXAMPLE VII SYNTHESIS OF Tl-IREO-ERYTHRO 3( Z-MERCAPTO- l -METHYLPROPYL)TI-IIO)-2-BUTANOL To a mixture of refluxing methanol (30cc) and diethylamine (15 drops) at 64C is added 0.8 grams of threo3-mercapto-2-butanolproduced according to Example II and 0.3 grams of trans2,3-butaneepisulfide produced according to Example IV. The refluxing is continuedat 64C for a period of 4 hours. The reaction mass is then allowed toremain overnight at room temperature after which period of time it isagain heated to 64C and remains at 64C for a period of 3 hours. When GLCanalysis indicates that most of the starting material is reacted theproduct is isolated via preparative gas liquid chromatography on an 8feet X inch glass 5% Carbowax 20M (polyethylene glycol-terephthalic acidterminated) column for mass spectral, NMR and IR analyses. The isolatedproduct is threo-erythro 3((Z-mercapto-l-methylpropyl) thio)-2butanolhaving the structure:

FIG. 5 is the NMR spectrum for this material. FIG. 6 is the infraredspectrum for this material.

EXAMPLE VIII SYNTHESIS OF TI-IREO-THREO 3 2-MERCAPTO- l-METI-IYL-PROPYL) TI-IIO )-2-BUTANOL To a refluxing mixture of methanol(30 cc) and diethyl amine cc) at 59C is added 0.8 grams ofthreo-3mercapto-2-butanol produced according to Example II and 0.3 gramsof cis-2,3-butane episulfide produced according to Example III (0.3grams). The reaction mass is refluxed for a period of 5 hours at 165964C, after which time it is allowed to remain at room temperatureovernight. The reaction mass is then reheated to 61C and allowed toremain at that temperature for a period of 3 hours after which GLCanalysis indicated that most of the starting material is reacted.

The major product is isolated via GLC (same conditions asExample VII)and analyzed via mass spectral, NMR and'IR'a'nalyses to be thethreo-threo 3((2-mercapto-l-rnethylpropyl) thio)-2-butanol having thestructure:

FIG. 7 is the NMR spectrum for this material. FIG. 8 is the infraredspectrum for this material.

EXAMPLE IX The following ingredients are refluxed for four hours:

Ingredient Parts L-Cysteine hydrochloride 0.9 Carbohydrate-freevegetable 30.9 protein hydrolysate Thiamine hydrochloride 0.9 Water67.30

EXAMPLE X To a portion of essentially flavorless salad dressing, theerythro-erythro form produced according to Example VI is added at therate of 1.0 ppm. The resulting product has a pleasant cooked onion note.The salad dressing is a mixture of the following:

Ingredient Parts Black Pepper oil 3 Nutmeg oil 3 Celery oil 3 Lemon oil3 Mustard oil I Vinegar-citric acid (50:50'mixture) I20 Starch pasteprepared from 300 tapioca flour-water (50:50

mixture) Liquid egg yolks 210 Sodium chloride 7 Sucrose l0 Mustard 20Locust Bean gum 6 EXAMPLE XI An imitation cheese flavor is formed bymixing the following ingredients:

Ingredient Parts Butyl butyryl lactate 2.0 lso-valeric acid 2.0 Ethylbutyrate 2.0 Butyric acid 3.0 Caproic acid l.0 Methyl amyl ketone 10.0Ethyl alcohol (95% aqueous 80.0 solution Propylene glycol 900.0

To the foregoing cheese flavor is added 1 part of the erythro-erythroform produced according.

The foregoing mixture is then added to cacciacavallo cheese in the ratioof 0.5%. The resulting blend is heated to a molten mixture (at 90C) andthen quickchilled at C over a period of one hour. The resulting cheesehas a cooked onion note.

EXAMPLE XII To the foregoing oil, five parts of the following mixture isadded:

Ingredient Parts 2.5-dimethyl-4-acetyl thiazole 4 Threo erythro formproduced 6 according to Example VII Ethyl alcohol 90 (95% aqueoussolution) The above material is added to an edible spun syntheticsoy-protein (manufactured by Swift and Company) at the rate of 0.02%.The resulting proteinaceous product has a distinct taste reminiscent ofbroiled liver.

EXAMPLE XIII A beef liver gravy is made by formulating a composi-Monosodium glutamate To one unit of gravy flavor concentrate, 8, ouncesof water are added, and the mixture is stirred thoroughly to dispersethe ingredients brought to a boil; simmered 18 for 1 minute and served.This meatless gravy exhibits a liverv like flavor.

EXAMPLE XIV The following ground sausage mixture is prepared:

Ingredient Parts Ground beef 200 Beef suet lce/NaCl (50:50 mixture) 200Potato flour 100 Anhydrous bread crumbs Dry milk powder 20 Standardspice flavor l0 containing:

Oil of cumin l.0 gm Oil of mustard 3.3 gm Oil of celery 3.3 gm Oil ofginger 5.2 gm Oil of cloves 14.6 gm Oil of coriander 17.6 gm Oil ofpimenta berries 22.0 gm Oil of black pepper 43.0 gm Oleoresin capsicum390.0 gm Oil of nutmeg 500.0 gm

To the above mixture, 0.02% by weight of the following mixture is added:

Ingredient Parts 2,4-diniethyl-5-ethyl thiazole 4 Threoerythro formproduced 6 according to Example VII Ethyl alcohol (95%) 90 The resultingmixture is then incorporated into a sausage and encased in the usualmanner. The encased sausage is heated in water at a temperature of -l80F for a period of 2 hours. This sausage has a liver-like notereminiscent of the taste of a sausage made with the addition of liver.

EXAMPLE XV A mixture of 8.8 gm of cysteine-hydrochloride, 8.8 gm ofthiamine hydrochloride and 300.0 of carbohydrate-free vegetable proteinhydrolysate is brought to a standard weight of 1000 grams by theaddition of water, and adjusted to 4.75 pH with acid or base asrequired. This mixture is then boiled under reflux conditions atatmospheric pressure for four hours and allowed to cool.

After the mixture is allowed to cool, 1 gram of erythro-threo formproduced according to Example VI is added thereto. The resulting mixturethus obtained has an excellent pot-roast like meat flavor.

EXAMPLE XVI Example VI This mixture is heated to 300F for 30 seconds.After cooling to 100F, 0.12 part of diacetyl and 0.10 part of hexanalare added. The resulting mixture has an excellent roasted sulfury meatnote.

gum arabic is added to provide a composition containing 0.5 parts gumarabic and one part flavor solid.

Ingredients Parts EXAMPLE XVII L-Cysteine hydrochloride 1.32 Thefollowing materials are homogeneously mixed at carb9hydatefi'eevegetable 0 protein hydrolyzate 77 F2 Ethyl thioacetate 22.00 Thiaminehydrochloride 1.32 Beta-Alanine 0.50 Ingredients Parts Water 52.81

Vegetable shortening 625.0 Salt 330.0 Glutamic acid 5.2 L-Cysteinehydrochloride 10.0 B. Preparation of Beef Gravy Glycine 5.2 5 I Beta-Alanine 1.3 A beef gravy concentrate is produced by formulating ofsodium inosinate 2 a gravy flavor composition of the ingredients and inthe and di-sodium guanylate amounts indicated:

Ingredients Parts The mixture is heated to 300F for 30 seconds. AfterFlour 34720 cooling to 100F, 0.12 parts of diacetyl and 0.10 partsCornstarch 36.00 B ff t 61.20 of hexanal are added. After aging theresulting mixture 3; chloride 930 for 3 hours, 4 parts of erythrothreoform of Example VI Monosodium glutamate 7.20 is addedEgioygtgfzegvegetable 19.80 The resulting mixture is aged for 10 hoursto provide Toasted onionypowder 250 a material having a sulfury, roastedmeat aroma. white P i The spray-dried product of 5.40 EXAMPLE XVlll (A)a. Cysteine hydrochloride in the amount of 8.8 gm is refluxed atatmospheric Pressure for To this mixture is added, at the rate of 4.0ppm, the four hours Wlth mlxmre of E of hydrolyzed erythro-threo form ofExample VI. The said thionol im- Vegetable Protem, gm thlamme Hclr 674proves the bloody, tangy beef extract flavor character gm of water.Subsequent to the reflux, the mixture f h mixtura is Cooled and 0ferythro-threo form Of EX- To one unit of aid gravy flavor concentrate 2ample V1 is added and Ultimately admlxed Wlth the ;ounces of water areadded, and the mixture is stirred composition. The mixture has anexcellent roasted, {thoroughly to disperse the ingredients, brought to aflav0rboil, simmered for 1 minute and served. The meatless The flavorP1'Cduced Example 15 added to: gravy obtained shows excellent bloody,tangy beef exl. a commercial dry type pet food; 40 tra t flavor. 2. asemi-moist type pet food; and 3. wet or canned pet food EXAMPLE XXI WhenS0 added at levels Of 0.5%, 1%, 1.5%, 2%, A Preparation of FlavorMixture; 2.5% and 3% (by vveight of foodstuff) highly palatable Thefollowing mixture is prepared: pet foods are obtained.

EXAMPLE XIX Ingredients Parts The composition prepared in Example XVI isdiszM ry -ibetwhydroxyethyl 53.0 solved in propylene glycol to provide a0.1% solution. 322; furrura] 5D This solution in the amount of 1.0 gm isadded to 7.3 Threo-threo form of 2.0 gm of a soup base consisting of: l5 Ingredients Pans T eii' h y i'i ti i sien-li-one Methional 1.0 Fineground sodium chloride 35.0 Hydrolyzed vegetable protein 27.8Tetrahydmfurfuryl alcohol Monosodium glutamate 18.0 Sucrose 11.0 Beeffat 5.5 B. Preparation of Soup:

u A beef noodle sou is re ared b mixin to ether: The composition ofExample XVI] (0005 gm) when p p p y g g added to the above soup basealso provides a soup hav- Ingredients Parts mg good meat flavor.

Sodium chloride 50 EXAMPLE XX lgliztxiligzleeof Part (A) of this 30Gelatin 10 A. Preparation of Spray Dried Product Monosodium glutamate 4The following ingredients are refluxed for 4 hours, aged for three daysand spray-dried to produce a solid White pepper. ground 6 ,producthaving a beef flavor. Before drying sufficient Mixed vegetable base 360Three cups of water are addedto the above mixture and this mixture isbrought to a full boil, simmered for five minutes and is then ready toserve The threo-threo form imparts a roasted garlic note to 5 the soup.Y

EXAMPLE XXII A. Preparation of Flavor Mixture B. Preparation of ShakeComposition A shake composition for enhancing the flavor of 25 meats isprepared by admixing the following ingredients:

Ingredients Parts Tumeric 25.0 Paprika 25.0 Oregano 15.0 Monosodiumglutamate 25.0 (fine grind) Sodium chloride (fine grind) 510.0 Mixtureof Part (A) of this 400.0

Example When sprinkled on meat, the above mixture imparts thereto agarlic and roasted note effect and this effect is caused by the presenceof threo-threo form.

EXAMPLE XXIII A. Preparation of Flavor Mixture The following mixture isprepared:

Parts Ingredients 4-Mcthyl-Sheta-hydrbxyethyl 55.0 thiazole Amyl alcohol10.0 Methional 2.0 Hexanal 5.0 Diacetyl 10.0 Ethyl disulfide- 3.0'Erythro-threo form of 1.0

Example VI B. Preparation of Shake Composition A Shake composition forenhancing the flavor of meats is prepared by admixing the followingingredients:

Ingredients Parts Tumeric 25.0 Paprika 25.0 Oregano 15.0 Monosodiumglutamate 25.0 (fine grind) Sodium chloride (fine grind) 510.0 Mixtureof Part (A) of this 5.0 Example Maltol dextrin 395.0

When sprinkled on meat, the above mixture imparts 35 thereto a roastedmeat note effect and this effect is caused by the presence oferythro-threo form.

What is claimed is;

l. A sulfur-containing compound having a structure selected from thegroup consisting of:

and

2. The sulfur-containing compound of claim 1 having the structure:

1. A SULFUR CONTAINING COMPOUND HAVING A STRUCTURE SELECTED FROM THEGROUP CONSISTING OF.
 2. The sulfur-containing compound of claim 1 havingthe structure:
 3. The sulfur-containing compound of claim 1 having thestructure:
 4. The sulfur-containing compound of claim 1 having thestructure:
 5. The sulfur-containing compound of claim 1 having thestructure: